Logstash ruby filter to parse our nginx multipart postdata

gistfile1.rb

filter {

  ruby {

      code => "# ruby filter to parse and extract postdata multipart encoded into fields

        if event['postdata']['request_body'] =~ /Boundary/

          fields = event['postdata']['request_body'].gsub('x0Dx0Ax0Dx0A', '=')
            .gsub('Content-Disposition: form-data; name=', '')
            .gsub('x0Dx0A', '')
            .gsub('--', '')
            .gsub('x22', '')
            .split('Boundary+0xAbCdEfGbOuNdArY')

        else
          fields = event['postdata']['request_body'].split('&')
        end

        fields.each do |f|
          unless f.nil? or f.empty?
            tmp = f.split('=')
            event['postdata'][tmp[0]] = tmp[1]
          end
        end

      "
  }
  
}